At what was billed as the final Ministry of Defence daily briefing of the conflict, he told journalists nobody was willing to trust Yugoslav President Slobodan Milosevic.

"We are not dropping our guard," said Mr Robertson. "We will still have
sufficient air forces available in theatre and on short notice to deter any
attempts at adventurism or intimidation, from whichever quarter."

In a later Commons statement, the prime minister described the G8 summit in Cologne as "successful and significant".

He told MPs that it had illustrated the improvement in relations with Russia, following earlier disagreements between Nato and Moscow over Kosovo.

Tony Blair says Nato 'faced down tyranny'

And he highlighted the speed of developments in Kosovo.

"The progress made in the few days since Milosevic finally caved
in has been extraordinary - on the withdrawal of Serb forces, on the deployment
of ours, on the role of the Russians, and now the agreement to demilitarise the
KLA," he said.

Mr Blair also reiterated that the UK would not provide aid to allow Serbia to rebuild while President Milosevic remained in power.

Renewing Russian relations

Earlier, addressing the MoD briefing, Foreign Secretary Robin Cook hailed the agreement for Russian participation in the peace implementation force as a firm basis for peace in Kosovo.

Speaking by video-link from the EU foreign ministers meeting in Luxembourg, he said the deal was also "a sound basis for renewing our very important relationship with Russia".

And he revealed that the Russian Foreign Minister Igor Ivanov had accepted his invitation to visit the UK next month for talks on strengthening ties between London and Moscow.

'Hope is now taking root'

Mr Cook, who plans to visit Kosovo later this week, said that there were already the first signs that life in the war-torn province was returning to some sort of normality .

Bakeries and other businesses in Kosovo have resumed operation

Farmers were back at work in their fields, buildings were being repaired, street markets were re-opening and starting to sell fresh produce.

"Hope is now taking root, " Mr Cook said.

He added: "It is those signs that the population of Kosovo is returning once again to their villages and homes and going about its business in peace which provide the reward for all of those who have taken part in the military campaign for the last three months."

The UK was prepared to do its bit to help reconstruct Kosovo to turn it into a peaceful and democratic society he said.

And he revealed that 60 UK police officers would be sent to recruit, train and monitor a new civil police force.

"A police force which will not feared by the local people as the Serb special police were, but a police force that they can regard as their guarantee of their personal safety and security," he said.

Final cost unknown

Mr Robertson said the government was still calculating the total cost to the taxpayer of the Kosovo conflict.

But he told MPs in the Commons that the costs of the UK forces' role in the Balkans
would be met from Treasury contingency reserves rather than from the defence budget.

Mr Robertson also said it was only now possible to begin to accurately estimate the cost of rebuilding Kosovo.

Some predictions have already put the final bill for reconstructing the region at $100bn.